Since I was post-whoring some else’s thread, I figured I should start my own.
It worked! Here's a link to a screenshot. CPU-Z is showing the specifics of the A105 motherboard while XP shows the T7600 CPU.
I upgraded a Toshiba Satellite A105-S4201 (Intel 945GM chipset) with a lowly Core Solo T1350 to a Core 2 Duo T7600. All I had to do in preparation was upgrade to the latest BIOS version (ACPI Flash BIOS version 6.00).
I used Arctic Silver 5 thermal paste after first cleaning the heat sink and CPU die surfaces with rubbing alcohol and a Q-tip. It posted fine so I went ahead and installed Windows XP Pro with all patches and drivers to see if there were any thermal issues under a load.
The CPU fan ramps up and down like normal. In fact, it seems to cycle with load exactly like the T1350 processor did. Most of the time the fan is running so slowly, it’s not audible. Even with only 512MB RAM installed, this puppy screams through the software install and Windows patches.
The CPU I used is a T7600 Core 2 Duo with a 667MHz FSB and 4MB L2 cache. I picked it up on eBay for $125. A T7200 or T7400 (also have 4MB L2 cache) would probably be just as fast for less money.
If anyone reading this wants to attempt a CPU upgrade, just make sure it is a Socket-M (aka mPGA478MT, aka Socket 479 mPGA ) CPU with 533MHz or 667MHz FSB. Socket-P and 800MHz FSB Socket-M CPUs will not work.
Hope this helps.